The eye is a complex assembly of various tissues that together function to receive and transmit light to the brain to enable vision. Eye function can deteriorate over time due to age, injuries, infections or various disease conditions resulting in impaired vision. Numerous procedures have been developed to treat various eye defects and conditions so as to improve vision. These include, for example, cataract surgery, refractive surgery including LASIK, trabeculectomy, vitreoretinal surgery, and intravitreal injection of pharmaceuticals. These eye procedures involve repeat placement, removal and exchange of various instruments, which must be accomplished with care, accuracy and precision while stabilizing the eye in order to avoid inadvertent incising of unintended ocular tissues.
In vitreoretinal surgery, for example, a trocar system is used through which instruments are introduced and exchanged throughout the procedure. Introduction and removal of the trocars during this procedure involve: (1) stabilizing the eye; (2) determining the correct trocar position in pars plana so as to avoid causing trauma to the natural lens or injury to the retina resulting in tears that can lead to retinal detachment; (3) dragging of the conjunctiva to achieve misalignment of entry points in conjunctiva and sclera; (4) removal of blade introducing the trocar; and (5) positioning the irrigation cannula. These steps are performed using multiple instruments that are exchanged during each step and for each sclerotomy—in the most common three-port pars plana vitrectomy surgery, these steps are repeated three times. As proper completion of these preliminary steps is crucial to initiating eye procedures in a safe and efficient manner, a great deal of time is taken to perform these steps, which therefore, account for a significant portion of the time involved in the procedure.
Furthermore, certain eye procedures do not require administration of regional anesthesia (its use can cause discomfort, bleeding or infection), movement of the eye, which can occur if no regional anesthesia is used, can interfere with proper placement, use and removal of various instruments thereby presenting a stability and safety issue.